Precaution number one- - - -install a seat belt/shoulder harness system. It takes a massive crash to push the steering column back far enough to injure a driver who is restrained properly. That's also a lot less work than redesigning the steering column with a collapsible section.
Jerry
Second Jerry's comment. Inertia is the culprit - body keeps going until something (the steering wheel for the driver) stops it. Much better if the seat belt stops one than the steering wheel (dashboard or windshield for passengers). I have a childhood friend that walked, for the last time, to his Opel Kadett and proceeded to drive without his seat belt being fastened into a horrible wreck. He has been in a wheel chair for over 30 years.
